Fix optionfiles parsing error with include directive

[garenchan]

For example, there are the following two option files:

D:\test\base.cnf

[mysql]
port = 1001

D:\test\my.cnf

!include D:\test\base.cnf

[mysql]
port = 1002

We expect the parsed port of my.cnf to be 1002, but we actually get 1001!

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[garenchan]

I have signed the Oracle Contribution Agreement (OCA).

[mysql-oca-bot]

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Thanks

[garenchan]

I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.

[mysql-oca-bot]

Hi, thank you for your contribution. Your code has been assigned to an internal queue. Please follow
bug http://bugs.mysql.com/bug.php?id=103546 for updates.
Thanks